Ruby is the latest hot language but it’s still comparatively young and still lacks much of the infrastructure you might expect it to have – a GUI library for instance. FXRuby is a Ruby extension based on the FOX C++ library. This maps application GUI objects to the native objects supported by a range of operating systems including Windows, Linux and Max OS. The attractions of FXRuby are its ease of use and cross platform development. Lyle Johnson, the author of this book, is lead FXRuby developer so he knows his stuff. The book starts with a description of how to install FXRuby and then goes on to a standard “Hello World” example. Then we are provided with a bigger example. Personally I would have preferred an explanation of how FXRuby is structured and a smaller example. After this we do move to a description of how the library works via an exploration of the facilities it provides mixed in with a little explanation of the underlying principles. The main problem with this book is that it doesn’t go very far and for all its gentle uncovering of principles it leaves you wanting more.